Twin Hawk

Released in June 1989.

There are several differences between Twin Hawk and its Japanese version Daisenpuu:
* Twin Hawk supports two simultaneous players.
* Daisenpuu supports two players, but only one at a time. Because of this, it also supports Cocktail cabinets.
* In Twin Hawk, both planes are purple and pink for player 1 and 2 respectively.
* In Daisenpuu, the planes are green for both players.
* In Twin Hawk, when you die, you continue the game at your current position.
To compensate this, they increased the health of bigger enemies and the rank/dynamic difficulty (enemies start shooting sooner and faster).
* In Daisenpuu, when you die, you continue the game at predefined positions.
* In Daisenpuu, big blue bullets are faster (like the ones in the first boss), making those attacks much more difficult to dodge.
* In Twin Hawk, small orange bullets (like the ones in the beginning) have worse visibility. In Daisenpuu they're more yellow and have better contrast against the background.